I found this on a technical blog dedicated to webos, made by a chinese researcher.

link to the blog
http://edu.bioinfoserv.org/zh/module...le.php/150/c34

刷机模式工具:用于无法开启刷机模式,基于windows环境运行。下载。
http://mirror.bioinfoserv.org/zh/upl...rush_mode..exe

A friend translated it with

"flashing tool to be used on phones that cannot be switched on".

... any one with a bricked pre3/etc willing to do some test ?